Question

|2x+5|=3

Answer 1

\(\Leftrightarrow\left[{}\begin{matrix}2x+5=3\\-2x-5=3\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}2x=-2\\-2x=8\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=-4\end{matrix}\right.\)

Answer 2

Giúp mình với

Answer 3

|2x – 5| = 3

TH1: |2x – 5| = 2x – 5 khi 2x – 5 ≥ 0 ó 2x ≥ 5 ó x ≥ 5/2 

Khi đó |2x – 5| = 3

=> 2x – 5 = 3 ó 2x = 8 ó x = 4 (TM)

TH2: |2x – 5| = - (2x – 5) khi 2x – 5 < 0 ó 2x < 5 ó x < 5/2 

Khi đó |2x – 5| = 3

ð - (2x – 5) = 3 ó 2x = 2 ó x = 1 (TM)

Vậy phương trình có nghiệm là x = 4; x = 1

Answer 4

TH1:

2x+5=3

2x= 3-5

2x=-2

x=-1

TH2:

2x+3=-5

2x= -5-3

2x=-8

x= -4

Answer 5

\(\left|2x+5\right|=3\)

TH1 : \(\left|2x+5\right|=3\)

\(2x=3-5\)

\(2x=-2\)

 \(x=-1\)

Th2 : \(\left|2x+5\right|=-3\)

\(2x=\left(-3\right)-5\)

\(2x=-8\)

 \(x=-4\)

Vậy \(x=\left[{}\begin{matrix}-1\\-4\end{matrix}\right.\)